This invention relates generally to can opening and liquid pouring means for use in the dispensing of liquids from sealed cans, and more particularly to such means primarily suitable for use in the rapid dispensing of engine oil from sealed cans, with minimal risk of spillage.
For many years, engine oil has been sold in quart-sized cans from which it can be poured directly into the oil filler openings of automobile, truck etc., engines. During this period, various types of can opening and dispensing devices have been proposed for use in the transfer of oil from these cans into such filler openings, some of which have included means for venting the cans to facilitate the outflow of oil therefrom. All such devices of which I am aware, however, have been designed to form vent holes improperly positioned for most effective performance and, in some cases, so poorly positioned as to present serious oil leakage problems. In this connection, U.S. Pat. No. 2,812,112 to Allen discloses a can opener and dispenser comprising a bar designed to fit diametrically across the top of a can fitted with a pouring spout at one end and a punch for venting the top of the can at the other end. The position of the vent hole made by the Allen device in the top of the can detracts from its effectiveness because it allows oil to block the hole and leak therethrough when the can is tilted to permit the pouring of its contents through said pouring spout. U.S. Pat. No. 3,134,506 to Way discloses another device attachable to an oil can to provide pouring and air vent openings in the top of the can. This device is subject to the same objection insofar as the position of the air vent opening is concerned as the Allen device. U.S. Pat. No. 2,547,556 to Benigar discloses a puncturing and dispensing device for oil cans adapted to punch an opening in one end of such a can through which the oil can be dispensed, and cut a second (air vent) opening in the opposite end of the can in line with the dispensing opening. The problem here is that when the can is tilted for the pouring of oil into the oil filler of an automobile engine, or the like, the oil level in the can is higher than the air vent opening, to again pose a problem of oil leakage. Each of U.S. Pat. Nos. 1,293,244 to Thayer et al. and 2,061,582 to Luthi discloses a liquid dispenser adapted to form pouring and vent openings in the same end of a can, hence is subject to the above-discussed oil leakage shortcoming of the Allen device. U.S. Pat. Nos. 2,099,323 and 2,105,575, both to Wiswell, teach can opening and dispensing devices with punch attachments for punching vent holes in the ends of oil cans. In each case, oil dispensing and air vent holes are of necessity formed in the same end of the oil can on which the device is used, so that the device is subject to the same criticism as the Allen device, and others of similar character, discussed above, insofar as oil leakage propensity of the air vent hole is concerned.
In addition to being poorly positioned for most effective transfer of oil from cans with minimal risk of leakage, the vent holes provided by the devices of the above-mentioned patents are all, because of the manner of operation of those devices, formed during the attachment of the devices to oil cans, and prior to the time any oil is poured from the cans. This, it seems to Applicant, is poor timing insofar as the venting of the can is concerned since it gives the user of any such device no opportunity to select the most opportune time for venting an oil can to gain maximum flow rate, with minimum risk of oil leakage, from the can.
There is thus, in view of the foregoing, a need for can opening and liquid dispensing means with cooperating means under the control of the user to give him the opportunity of venting a can at the optimum position and time to achieve the fastest outflow of oil therefrom with little or no risk of oil leakage at the vent hole. Such venting means under the control of the user should ideally permit him to form an air vent hole above the oil level in the can after only a small amount of the oil has been dispensed to insure emptying of the can in the shortest period of time. This need for a can opening and oil dispensing device with air venting means for optimum effect position-wise and time-wise has never been satisfied, or even recognized, insofar as I am aware.
In spite of the fact that oil can opening and liquid dispensing devices with air vent puncturing means have been known for some time, as evidenced by the above-referenced patents, no such device has ever been, to my knowledge, in widespread usage, possibly because of the above-discussed oil leakage disadvantages thereof. Motor oil is generally dispensed from cans by means of attachable oil can spouts that cut pouring openings in the cans but do not form air vent holes therein. As a result, the oil cans drain annoyingly slow, forcing the users of such oil can spouts to stand impatiently by, or find other things to do, until the cans are empty. Means for providing a properly positioned air vent in the can, at such time as risk of oil leakage through the vent is passed, would greatly speed up the process of adding motor oil to a car engine and allow such oil addition to be accomplished without interruption or an aggravating wait for the sluggish draining of oil from one or more cans.